Characterisation of dihydroazulene and vinylheptafulvene derivatives using Raman spectroscopy: The CN-stretching region.

The effect of adding electron donating and withdrawing groups on the dihydroazulene (DHA)/vinylheptafulvene (VHF) photochromic system has been investigated using Raman spectroscopy in CS2 solutions. The photoswitching between DHA and VHF is often characterised with UV-Vis spectroscopy. However, Raman spectroscopy can also be used for this purpose and give structural insight, as the light induced ring-opening from DHA to VHF causes changes in the CN-stretching frequencies.

Stones in the lacrimal gland: a rare condition.

Purpose: Stones (dacryoliths) in the lacrimal drainage system are relatively common. However, stones in the lacrimal gland itself are very rare. We present three cases of lacrimal gland stones and describe the clinical and histopathological characteristics and composition of the stones.

Fourier transform Raman difference spectroscopy for detection of lignin oxidation products in thermomechanical pulp.

Spruce thermomechanical pulp (TMP) was oxidized by the 2,2'azinobis-3-ethylbenzthiazoline-6-sulfonate cation radical (ABTS*+) in the presence and absence of oxygen. The pulp modification was monitored by Fourier transform (FT) Raman difference spectroscopy and other nondestructive spectroscopic methods. The ABTS*+ oxidative system resulted in modifications very similar to the laccase-ABTS-oxygen system, except for the FT-Raman results, which showed a difference in mechanisms attributed to a difference in produced Raman bands.

Melanoma diagnosis by Raman spectroscopy and neural networks: structure alterations in proteins and lipids in intact cancer tissue.

Melanoma is the most aggressive skin cancer. The specificity and sensitivity of clinical diagnosis varies from around 40% to 80%. Here, we investigated whether the chemical changes in the melanoma tissue detected by Raman spectroscopy and neural networks can be used for diagnostic purposes.